A new approach to the particle-in-cell method for the computation of three-dimensional incompressible unsteady flows

A hybrid three-dimensional particle-in-cell (PIC) method is proposed. This 3D PIC technique combined with a classical three-dimensional vortex particle method is applied to the calculation of unsteady inviscid and incompressible flow. More precisely the wake roll-up behind an inclined flat plate is studied. A spreading procedure of the vorticity, a direct interaction between nodes of the grid and a mesh generated from the plate discretization present a few undesirable grid effects, but ensure a continuous application of the slip condition to the plate. In this way the total circulation is nearly conserved and, in the case of a separated flow at high angle of attack, the particles are prevented from crossing the wing. Numerical results are compared with experiment for several angles of attack and aspect ratios.